With the advance of Internet of Things (IoT) in the current society, various small wireless communication devices are spreading. Along with this trend, various low power consumption devices such as one for remote monitoring in a factory or wireless tags carried by elderly people and children to inform their locations are becoming widespread. Accordingly, techniques of wirelessly supplying power to these devices have been widely developed. As a technique of automatically supplying power, there is a known technology of supplying power wirelessly using radio waves. For example, there is a technology of communicating between a power supply apparatus and a power receiving terminal to detect an arrival angle of the radio waves so as to control a power supply signal beam. In this case, there is a study of a technique to estimate a direction of the arrival of the radio waves at the timing of receiving the signal from the power receiving terminal on the power supply apparatus, and thereafter direct the power supply signal beam toward the estimated direction.
Such a power supply apparatus, however, performs power supply after estimating the direction via wireless communication. That is, wireless communication and wireless power supply need to be performed serially. This makes it difficult to perform wireless communication during wireless power supply, which is inefficient compared with a case of simultaneously performing both wireless communication and wireless power supply. In addition, there is a need to transmit a position estimation signal for estimating the direction of arrival, consuming extra time and power correspondingly. Furthermore, it is necessary to provide an antenna for power supply separately from the antenna for communication.